⬆ Upgrade Starlette from 0.17.1 to 0.18.0

[Kludex]

For reference, set of changes that broke FastAPI:

• Update type annotations for BackgroundTask and utils encode/starlette#1383 (mypy)
• Don't set headers for responses with 1xx, 204 and 304 status code encode/starlette#1397
• Don't omit Content-Length header for Content-Length: 0 cases encode/starlette#1395

Related to #4477

[codecov]

Codecov Report

Merging #4483 (25feb07) into master (146f57b) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master     #4483   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          531       531           
  Lines        13627     13630    +3     
=========================================
+ Hits         13627     13630    +3     

Impacted Files	Coverage Δ
fastapi/concurrency.py	100.00% <100.00%> (ø)
fastapi/dependencies/utils.py	100.00% <100.00%> (ø)
fastapi/routing.py	100.00% <100.00%> (ø)

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[github-actions]

📝 Docs preview for commit e5c9343 at: https://61f176cddc1930f5b39fe9cd--fastapi.netlify.app

[Kludex]

@tomchristie FastAPI uses a Response object that travels through the dependencies, but that Response is not the response that will be returned at the end. There's a "cleanup" after the dependencies are solved. You can see the "cleanup" logic below:

fastapi/fastapi/routing.py

Lines 216 to 254 in 291180b

	solved_result = await solve_dependencies(
	request=request,
	dependant=dependant,
	body=body,
	dependency_overrides_provider=dependency_overrides_provider,
	)
	values, errors, background_tasks, sub_response, _ = solved_result
	if errors:
	raise RequestValidationError(errors, body=body)
	else:
	raw_response = await run_endpoint_function(
	dependant=dependant, values=values, is_coroutine=is_coroutine
	)
	if isinstance(raw_response, Response):
	if raw_response.background is None:
	raw_response.background = background_tasks
	return raw_response
	response_data = await serialize_response(
	field=response_field,
	response_content=raw_response,
	include=response_model_include,
	exclude=response_model_exclude,
	by_alias=response_model_by_alias,
	exclude_unset=response_model_exclude_unset,
	exclude_defaults=response_model_exclude_defaults,
	exclude_none=response_model_exclude_none,
	is_coroutine=is_coroutine,
	)
	response_args: Dict[str, Any] = {"background": background_tasks}
	# If status_code was set, use it, otherwise use the default from the
	# response class, in the case of redirect it's 307
	if status_code is not None:
	response_args["status_code"] = status_code
	response = actual_response_class(response_data, **response_args)
	response.headers.raw.extend(sub_response.headers.raw)
	if sub_response.status_code:
	response.status_code = sub_response.status_code
	return response

I've selected the whole snippet, from the point we get the Response object used in the dependencies (solve_dependencies call) until the last 5 lines (on which the values from Response are passed to the actual response object that will be used.

This comment is JFYK, I don't expect any action to be taken on Starlette. Also, considering that FastAPI tweaks Starlette internally for some features it has.

[github-actions]

📝 Docs preview for commit 8d10fca at: https://61f178c33b56fbf00cd761e2--fastapi.netlify.app

[Kludex]

We added ParamSpec to run_in_threadpool on Starlette. The error here was:

fastapi/routing.py:129: error: "<nothing>" object is not iterable  [misc]

[github-actions]

📝 Docs preview for commit fb2fdf5 at: https://61f17c4d603b5ade0e34ca0d--fastapi.netlify.app

[yezz123]

@Kludex 🌟

[L1ghtn1ng]

can this get merged soon and released please?

[ShadowLNC]

Starlette 0.19.0 has now been released, not sure if it's worth performing a further upgrade here, or leaving that for another time.

[Kludex]

As per history, Sebastián prefers to bump progressively. Also, those two releases have a lot of changes.

[Net-Mist]

Hello !
I would like to know more regarding the status of this PR. Is there a reason not to merge it ?

[Kludex]

Hello ! I would like to know more regarding the status of this PR. Is there a reason not to merge it ?

Let's wait for @tiangolo :)

[github-actions]

📝 Docs preview for commit e7087f5 at: https://62743b753fbbb2094bed5235--fastapi.netlify.app

[github-actions]

📝 Docs preview for commit 25feb07 at: https://62744bdcedfeb0165d6951ed--fastapi.netlify.app

[tiangolo]

Awesome @Kludex, thank you! 🙇

I added a filterwarning for pytest complaining about Cryptography so we can run tests while reaching the version that drops support for Python 3.6.

This will be available in the next release in a couple of hours, FastAPI 0.76.0 🏷️